Prior art seating grommets have comprised relatively massive, solid, hemispherical components of a flexible material such as rubber. See, for example, U.S. Pat. No. 2,225,472. The grommet would be provided with a groove for engaging a wall, usually combined with a flange for inhibiting pull-through. Such grommets frequently required a setting force of up to 75 pounds. As the areas in which these grommets have been employed have been reduced in size (for example, in automobiles) it has become more difficult to find the room necessary to exert such pulling force. Improved grommets having a lesser setting force have been proposed wherein the flexible portion is substantially hollow. Examples of the latter grommets are shown U.S. Pat. Nos. 2,375,373; 3,244,802; 3,372,960; 4,041,241; 4,685,173; 5,337,447; 5,452,494; and 5,732,440. The latter two patents are assigned to the assignee of the present invention. While some of these latter grommets worked well in certain situations, it has become necessary and desirable to reduce the insertion or setting force still further, so that seating grommets could be sued in even smaller environments.